The Golden Age of Sample Return Missions from Space

UCLA Meteorite Gallery Lecture Series: October 2020
Title: The Golden Age of Sample Return Missions from Space: What Comet Samples Have Told Us About the Origin of the Solar System
Lecturer: Dr. Donald Brownlee, University of Washington

In the past 15 years, space missions have returned samples of the Sun, a comet and an asteroid for detailed study by state-of-the-art methods in laboratories around the world. Samples from two additional asteroids are being returned by current missions and return missions from the Moon and Mars are planned. Starting 30 years after the last Apollo lunar mission, some have called these new missions the Golden Age of post-Apollo sample return missions.

In this talk, I will describe the Stardust mission and how the ancient rocky materials it returned from an active comet have given us important new insight into the formation of icy-bodies near the edge of the solar system. Just as Moore’s Law led to vast improvements in our computers, analogous advances in microanalytical methods have led to unprecedented capabilities for studying extraterrestrial materials. In the case of comet samples, the analyses have found abundant rocky materials that formed at incandescent temperatures, probably in the inner solar system. Such materials were profoundly unexpected components in a body whose ices formed at cryogenic temperature. Their presence in comets is evidence of large scale transport of rocky materials from the hottest regions of the early solar system to its coldest parts.